1. Field of the Invention
The invention relates to carpet and fabric cleaning compositions, and more specifically to a carpet cleaning composition that includes a combination organic solvent and fragrance. In one of its aspects, the invention relates to a carpet cleaning solution that includes an organic, citrus based, low volatility cleaning solvent.
2. Description of the Related Art
Conventional carpet and upholstery cleaning compositions typically contain anionic and/or nonionic surfactants, an anti-soiling agent such as polymerized styrene/maleic anhydride, a solvent such as glycol ether, and a fragrance to impart a pleasant scent. Known carpet cleaning compositions are disclosed in the Campagna et al. U.S. Pat. No. 5,955,413 and Scialla et al. U.S. Pat. No. 5,928,384, both of which are incorporated herein by reference. Examples of commercially available cleaning solutions include: BISSELL Fiber Cleansing Formula, Hoover Steam Vac carpet/upholstery detergent, Dirt Devil carpet & rug shampoo, Rug Doctor Steam Cleaner, and Full Release Professional Carpet Cleaner by Oreck. The BISSELL Fiber Cleansing Formula comprises water; an anti-stain agent; an acrylate copolymer that functions as an anti-soil agent and a pH adjusting agent; an alkyl naphthalene sodium sulfonate, which is an anionic surfactant; a blend of two alkoxylated lineal alcohols, which is a nonionic surfactant; a trace of an anti-foam agent; and a fragrance.
Carpet cleaning compositions should be stable and essentially free of volatile solvents, yet have a pleasant fragrance the remains with the carpet after cleaning. The fragrance qualities of liquid commercial products are greatly dependent on the plethora of volatile and semi-volatile organic compounds contained therein. However, volatile organic compounds are known to deplete naturally occurring ozone in the upper atmosphere and are thus desirably avoided. Also, a small segment of the population is hypersensitive to even the slightest exposure to volatile organic compounds.
A fragrance having low volatility is d-limonene, commonly known as citrus oil. d-Limonene is also an effective solvent for cleaning products. U.S. Reissue Pat. No. 36,982 to Melikyan et al. discloses a cleaning composition for a variety of industrial and household applications, including cleaning and removing spots from carpets, and comprising d-limonene and hydrogen peroxide. The background section of Melikyan “982 states that many other patents disclose the use of d-limonene, which provides a pleasant citrus-like aroma, as well as cleaning properties. Other cleaning compositions containing d-limonene are disclosed in U.S. Pat. No. 4,511,488 to Matta and U.S. Pat. No. 4,620,937 to Dellutri. The Matta '488 composition is said to be suitable for hard and/or flexible substrates and contains a minimum of 7.8 wt. % d-limonene. The concentration of d-limonene in the Dellutri “937 composition varies according to its purpose, and the preferred d-limonene concentration is 60 vol. %. The Dellutri “937 composition is said to be useful for cleaning carpets.
U.S. Pat. No. 6,326,344 to Levitt discloses a carpet cleaning composition that contains little or no surfactant for good emulsification and, thus, leaves no tacky residue upon drying. The composition comprises about 50–98 wt. % water, about 0.05–2 wt. % acid copolymer emulsifier, about 0–1 wt. % of at least one surfactant, and about 1–50 wt. % of at least one solvent. d-Limonene is listed as one of the many preferable water-insoluble solvents. Additionally, the composition may contain a buffer to maintain the pH of the composition within the range of about 4 to 10.
U.S. Pat. No. 6,048,368 to Tcheou et al. discloses a cleaning method of treating a spot or stain on a textile fabric comprising the steps of applying a detergent composition to the spot or stain, placing an absorbent layer to one side of the textile fabric, and applying heat and pressure to the opposing side of the textile fabric so that some or all of the spot or stain is absorbed into the absorbent layer. The detergent composition contains 3–90 wt. % hydrophobic solvent, 5–50 wt. % surfactant, and 5–92 wt. % water. d-Limonene is a preferred solvent.
U.S. Pat. No. 4,304,675 to Corey et al., U.S. Pat. No. 4,566,980 to Smith, and U.S. Pat. No. 4,873,000 to Weller all disclose various solid/dry carpet deodorants or treatments with citrus as a desirable fragrance.
In addition to the above patents, the use of d-limonene in carpet cleaning compositions in addressed in the article, “d-Limonene Bears Fruit,” from the November 1998 issue of Cleanfax magazine. The article states that d-limonene “is experiencing growing acceptance as the solvent of choice for a number of cleaning applications. It is finding its way into steam cleaning, carpet shampoos, and spotting agents.” The article further explains that d-limonene is a popular replacement for previously common solvents in the textile cleaning industry due to its low environmental impact and its fresh natural odor.
Furthermore, it is desirable to create a stable carpet cleaning solution that includes normally incompatible components such as terpene hydrocarbons, polysiloxane derivatives, and sulfo-methacrylic polymers without using excessive amounts of surfactant or co-solvents to achieve stability. Unstable formulations tend to create solids that separate and settle out of solution. A stable formulation maintains a liquid mixture without the formation of solids.